Driving mechanism for machine tables



March 5, 1946. v L. ROBACZYNSKI 1 2,396,123 DRIVING MECHANISM FOR MACHINE TABLES Filed Ma 26, 1943 2 Sheets-Sheet 1 UNVENTORQ A T T ORA/E Y6.

ZAD/SLA w Rog/4' czY/vs/r/ March 5, .1946. L. ROBACZYNSKI 2,395,123-

' I DRIVING MECHANISM FOR MACHINE TABLES Filed ma 26, 1945 2 Sheet-Shet 2 II I I g 3* ll INVENTOR. LAD/54A as Roe/1C2 YN-$/f/.

ATTORNgYs.

Patented Mar. 5, 1946 UNITED PATENT "OFFICE 2,396,128 l hemp-1G*ntcnms lfF-ot-mtfim TABLES Ladislaus Robaczynski;Brooklyn;N. Y. 'itttaatatmytt, 194s,"seria1 No. 18;520

. This :invention'are'lates 7170 "new: and useful. improvements in driving .mechanisms fo the"tables of surfacegrinders {andsimilar machines of the ype-in which: a work A carrying tableris :reciprocated withrelation to a tool, which performs; operations upon the work carried rbytasaidtable.

One object of the present invention is to improve the construction "and "mode of operation of such driving mechanismsgmore particularly "with respect to themanual operationithereof.

' It is another :object :of rtheiinvention to provide a :novel construction which eliminates all shocks and jars incidental :to the reversing of the direction of travel of the work supporting table, thus reducing to :fatminimum, "the vibration inherent inmachines =of .this'ctypei'as generally constructed. e i

It is a further object ofthe invention tniproride a novel combination power "actuated "and manually operated .table driving mechanism .in which that portion of the mechanism which is power actuated may be 'operatively'tdisconnected with the table when it is desired to operate the same manually.

The invention has been iherein illustrated as embodied in a surface grinding machine but it is to be understood that it i-s n'ot to be limited to such machines since it is applicable to machines of any type in which it is desirable to operate a work supporting table either by hand "or power. ,In the-accom-panyingdrawings, ,Y I

Figure 1 isa horizontalzse'cti'ona'l Viewbf -a surface grinding machine; illustrating] the improved mechanism embodied therein and its ree lationfto the several driving mechanism for suchmachines,

Figure 2 is a view in. elevation :partlyr-broken away and Partly section taken substantially on the line -2-+2' of Figure 1, 'p 7 Figure 3 is a fragmentarysectional'view take'n substantially on the line 3-3 of Figure 2; and; Figure 4 is'a ,distended' perspective view.illustrating the-detail construction of a clutch mechanism employed 5 in connection with the driving mechanism; e 1 n l, Referring to the drawings by reference ,character, l desi nates the framezcf the. machine.

The frame J0 is preferablyin the j'formofa housing, rectangular in'cross sectional form and the front wall thereof is designated H. Y e

'Iwo trackways 13 extend from frontto rear of the top wall of the frameandslidably' mounted upon these trackways I3, there is a saddle i4; ro d d .t @29 ;v its wid r fac it t acks 1 for sliding engagement with thetrackways i3;

elements of a nonventional 1 Extendingl iromlleft to:rightpf thej tqptface of the saddle I 5 there are Figure f the drawof which is illustrated in ings" 2; -S1idably mounted in the trackways lli for -reciproeating movement there isa work 0a :ying table 11, the under face of which has tracks lB for -slidably mounting the table in the trackwaysl6,heretofore;mentioned. M 3 The saddle-l4 serves t move the tabl and the work -carriedthereby intermittently with wrespect to a grinding wheel or other tool to prejs'ent surfaces thereof successively to ;the; tool-by a mechanism not herein illustrated since-it forms nolpart of'the presentinventiom l; he work, su p in tt b e is 'rduri ez nsmtion of the machine, -re ciprocated constantly relative to the grinding wheel or .901; and-itis the mechanism for p tin th .wor sup rt n table which :form the subject matter of thisapplication. V V r H Upon-the exterior oft-the 10, there is ,a housing [Bland mounted Within this housingpthere is a motor20. Mounted upon the shafto'f the motor :20 there is a driving;pulley 2 l Mounted in the rear wall ofthe frame Ill-in bearings 'Zithere is. a shaft .which carries/ a driven pulley ,23 upon its outer end-and- -a gea r 26 upon its opposite or inner end. belt, 2;2 passesaround the pulleys 2lwand-23 andserves todrive the latterand the shaft 25. g l; v Meshingwith, thegearZG there is agear zl. This gear is carried by a shaft 28:w hich is mount ed at one end in a bearinglfl vupon \theinn er face of the rear wall of theirame l0. -I7heppposite end of the shaft 28 .is mounted in a bearing 30 mounted. in a bracket 3lwhich extends wardly from theright hand sidewall or the frame [0. This end of the shaft/28 extends slightlyvhe yondjthe bearing 311 as at 32 and :carries thegear 33 of a conventional automaticlreversing mechanismq34 which operates to reverse the direction ,of rotation of the table driving gear toimpart to the work supporting table, H the reciprocating motion,heretofore mentioned. a Theshaft 31 of the automatic reversing gear 34 is mounted in bearings35 in the inner ends oftwo brackets 36 which extend inwardlyof the front wall ofthe frame H]. r; l t The ,shaft -31 hasan extensions38 which-is mounted in abearing 3.9 -in a bracket Which also extends inwardly ,of the front wall l|.-..er the frame lflandthis. extension 38 carries upon it's free end, a bevel gear 4 I.

\Mounted in the front and tar wells er the r a w l-tititt lr ame frame I as at 42 and 43 respectively there is a long cylinder gear 44 the forward end of which is operatively connected with a gear 45. This gear meshes with and is driven by a small gear 46 which latter gear, since it forms the means for driving the gear 45 and the cylinder gear 44 when operated either manually or by power, will be hereinafter referred to throughout the specification and claims as the driving gear.

Carried by the under face of the table I1, see Figure 2, there is a rack bar 41 and meshing with the rack bar 41 there is a gear 48. This gear 48 is mounted in lug bearings 49 depending from the under face of the saddle I4. The gear is positioned in an opening 50 in the saddle, indicated by dotted lines in Figure 2 and as also illustrated in said figure, the gear 48 meshes as at I with the cylinder gear 44.

By this construction, as the driving gear 46 is operated, either manually or by power, the gear 45 will drive the cylinder gear 44 which in turn will drive the gear 48 to operate the work supporting table I1 through the medium of the rack 41.

Having thus described the manner in which i the work supporting table is operated by the driving gear 45, the manner in which the driving gear 46 is power operated by the automatic reversing gear 34 and also the manner in which it is operated manually and independently of the said automatic reversing gear will now be described.

The driving gear 45 is mounted upon a shaft 55, see Figure 3, to which it is operatively connected by a set screw or the like 50. This shaft 55 is mounted in a bearing 51 in a bracket 58 which extends inwardly from the left hand side wall of the frame I0, see Figure 1.

Referring again to Figure 3, the forward end of this shaft extends through an opening 59 in the front wall I I of the frame I 0 and this forward end is formed with an axially extending recess 60.

The reference character 6| designates a crank which has a shaft extension 62 which is adapted to project into and have sliding movement in the axial recess 60 of the shaft 55. The shaft extension 62 has an intermediate portion 63 of reduced diameter which construction provides two shoulders 64 and 65.

Sliding movement of the shaft extension 62 relative to the shaft 55 is limited by means of a screw or the like 66 carried by the shaft and extending into the space between the shoulders 1 64 and 65 of the shaft extension 62.

The crank 6| is provided with clutch teeth 61 which are adapted for engagement with clutch teeth 68 in the outer end of the shaft 55 for operatively connecting the crank GI to the shaft, thereby to rotate the latter.

The shaft 55 is provided with a reduced portion 59 and a reduced screw threaded extremity 10. A clutch member H is loosely mounted upon the reduced portion 99 of the shaft 55 and is retained thereon by means of a sleeve 12 which in turn is retained on the shaft 55 by a washer 13 and a nut 14 which latter has threaded engagement with the threaded portion of the shaft 55.

Extending forwardly of the shaft 55 from the clutch member 1 I, there is a sleeve-like extension which has a threaded end portion 16. The threaded end 16 of the sleeve-like portion 15 of the clutch member 1| extends to and abuts with the shoulder 11 formed by the reduced portion 69 of the shaft 55.

By this construction, it will be apparent that the clutch member 1| and the sleeve 12 are retained in position against movement longitudinally of the shaft 55 by the washer 13 and the nut 14.

The sleeve 12, heretofore mentioned, is provided with an internal keyway 18, see Figure 4, for the reception of a key 19, shown in dotted lines in Figure 3, which construction serves to connect the sleeve operatively with the shaft 55.

Slidably mounted upon the sleeve 12 there is a clutch collar 80. This clutch collar is operatively connected to the sleeve 12 by a key 8! which engages in keyways 82 and 83 respectively in the sleeve 12 and the clutch collar 80.

The clutch collar 80 has an annular channel 84 and clutch teeth 85 which are adapted for meshing engagement with clutch teeth 86 on the clutch member 1 I.

For moving the clutch collar 80 into and out of clutching engagement with the clutch member 1!, a hand crank 85, see Figure 1, is provided. The hand crank 85 is secured to a shaft 85 by means of a set screw or the like 81 and the shaft 80 is connected to a disk-like member 88 which operates in an opening 89 in the left hand side wall of the frame I0.

Eccentrically disposed with respect to the member 88 and extending therefrom, there is an arm 50 the inner end of which projects into the annular channel 84 of the clutch collar 80.

The hand crank 85 is provided with an operating handle 9I which is provided with an extension 92 the inner end of which serves as a pawl for engagement with either of two recesses 93 and 94 to retain the hand crank in either position to which it may be moved. The pawl is retained in engagement with the recess in either position by means of a spring which tends at all times to move the pawl into recess engaging position.

From the foregoing it will be apparent that with the hand'crank in the full line position in Figure 1, the clutch collar 80 will be disengaged with the clutch member 1I. When, however, the hand crank is moved to the dotted line position in Figure 1, the clutch collar 80 will be moved into operative connection with the clutch member H by reason of the eccentric position of the arm with relation to the axis of the shaft 86.

The reference character I00 designates a beveled gear which is loosely mounted for limited rotary movement upon the sleeve-like portion 15 of the clutch member 1 I.

As best illustrated in Figures 1 and 4, the hub portion ml of this gear is provided with a flange I02 which has a cut out portion I03 forming two shoulders I04 and I05.

Projecting from the clutch member N there is a radially off-set lug I06 which has an axial tongue extension I01. This axial tongue extension I01 occupies a position within the cut out portion I03 of the flange I02 and is adapted to cooperate alternately with the shoulder I04 and I05 to operate the clutch member H and the shaft 55 in opposite directions when the clutch collar 80 is operatively connected with the clutch member 1|.

The beveled gear I00 is retained in position upon the sleeve-like portion 15 of the clutch member by means of a friction disc or plate I I 0, a spider-like spring washer I II and two nuts H2 and II 3, the nuts having threaded engagement with the threaded portion 16 of the sleeve-like portion 15.

The degree of frictional engagement of the friction disc or plate III) with the bevel gear I00 agaoems:

issde'termined by. the tension under which; the

spider-like spring washer is placedbyithenuts 1 I21.

, 38 of the shaft 31 and that'during'such timeias.

the motor 20 is operating; the bevel' gear 100 will be continuouslydriven.

It is also to be noted, however, that unless the clutch collar 80 is 'operativelyconnected with the clutch member II, the shaft 55 will not be driven by power forthe reason that the clutch member II and the beveled gear I are free to turn together upon the shaft.

Therefore, when the clutch member II is dis-,- engaged with the clutch collar 80, the shaft 55 is free for turning by means of the hand crank 6|.

With the parts in this last described position manual operation of the shaft 55 by engaging the clutch teeth 61 with the clutch teeth 68 will operate the driving gear 45, the gear 45, the cylinder gear 44 and the gear 48 to operate the table II in either direction entirely independent of the poweroperating means and whether or not it is under motion by the motor 20.

If it is desired to operate the work supporting table II by power, it is only necessary to move the hand crank 85 from the full line position in Figure l to the dotted line position in said figure. Such movement of the hand crank 85 will throw I nenheretdforede'scribdbypowerrthe-shock cidental rto :throwing the. load onto: the beveled gear. I.00"will berelieved bya slipping of said'rbe elecligear I00'relativerto the'sleeve-like' extensionl'i 'of the: clutch member, thisrslippage being permittediby the friction 5 disc or .plate: I I0- and the spring'washed II I} .Referring: again to Figure 1,-upon reversalifo'f thedirection ofzrotation of the beveled gear I00 to: the: counter cloickwise direction, the :shoulder I04 passes out of: engagement with" the tongue M6 the shoulder I-05m0vesinto engage'ment therewith to rotate the clutch member II in the counter-clockwise direction.

During the slight interval between disengagement of the shoulder I05 with the tongue I06, the work supporting table would be at rest at the end of one of its movements. 7 I

As the shoulder I05 comes into engagement with the tongue I06, the shock incidental to I throwing the load of the work supporting table upon the beveled gear I00 is relieved by-a'slippage of said beveled gear which slippage is permitted again by the friction disc or plate II 0 and the spring washer I I I.

It has been found in actual practice that the flexible coupling above described eliminates almost ,entirely the vibration and jar incidental .to the reversal of direction of movement of the the clutch collar 80 into clutching engagement with the clutch member II which is driven by the beveled gear I00 through the medium of either of the shoulders. I04 or I05 and the tongue I01, depending upon the direction of movement of said beveled gear.

Rotation of the clutch collar 80 drives the sleeve I2 through the medium of the key 8|, the sleeve I2 driving the shaft 55 through the medium of the key I9. Rotation of the shaft 55 drives the driving gear 46 which in turn drives the cylinder gear 44, through the medium of the gear 45, the cylinder gear 44 in turn driving the gear 48 to move the table.

As heretofore stated the reversing mechanism 34 is automatically operated in the conventional manner to drive the shaft 38 and the beveled gear I00 in opposite directions to effect reciprocation By reason of the fact that there is a certain 7 amount of play or lost motion between the clutch collar 80 and the clutch member II, which play or lost motion occurs each time the direction of rotation of the beveled gear I00 is reversed, a yielding coupling between the beveled gear I00 and the shaft is provided.

For example, with the parts in'the positions in which they are shown in Figure 1, upon starting the motor, the beveled gear I00 would be rotated, but the shaft 55 would not be driven since the clutch collar 80 is not operatively connected with the clutch member I I. I

Upon starting the motor, assuming that the reversing mechanism is so positioned as to drive the beveled gear in a clockwise direction, the shoulder I04 will engage the tongue I06 of the clutch member II to rotate the latter also in the clockwise direction.

clutching engagement with the clutch member II to drive the work supporting table, in the manwork supporting table and that machines so constructed will operate with a higher degree of efliciency in precision grinding than it ispossible to attain 'with surface grinders as generally constructed.

It will also be appreciated that the present construction and arrangement of parts permits of manually operating the driving gear 46 entirely independent of its power operating means and also whether its power operating means be in motion or at rest.

This also is an important feature of this invention since in all surface grinding machines with which I am familiar, it is necessary to shut off the power in order'to drive the work supporting table manually and in such machines the manual operating means includes also, the entire power o erating gear train and the reversing. mechanism.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent of the United States, is:

1. In a manually and/or power operated driv- 7 and the first of said clutch parts at one side of the gear, a torque actuated slip device interposed between said reversing gear and said first clutch part at the other side of the gear, and the second of said clutch parts being connected with said shaft sodas to be moved axially thereof and to cause rotational movement thereto when engaged with said first clutch part and said reversing gear is in operation.

2. In a manually and/or power operated driving mechanism as set forth in claim 1, and manually operablemeans to retain the second clutch part engaged with or disengaged from the first clutch part.

3. Ina manually and/or power operated driving' mechanism, a rotatable shaft, cooperative driven and drive clutchv parts, a sleeve'loosely keyed on said shaft, means on said shaft which coacts with said sleeve to hold said driven clutch part on the shaft against axial movement with 5 respect to the shaft and allowing it to turn with a respect thereto, said drive clutch part being slidably keyed to said sleeve, a power driven gear loose on said driven clutch part, a lost motion connection between said gear and the driven clutch part at one side of the gear, a torque actuated friction slip device coacting with said driven 10 the shaft is being power driven as aforesaid.

LADISLAUS ROBACZYNSKI. 

